More and more devices are being replaced with autonomous and semiautonomous electronic devices. This is especially true in the hospitals of today with large arrays of autonomous and semiautonomous electronic devices being found in operating rooms, interventional suites, intensive care wards, emergency rooms, and the like. For example, glass and mercury thermometers are being replaced with electronic thermometers, intravenous drip lines now include electronic monitors and flow regulators, and traditional hand-held surgical instruments are being replaced by computer-assisted medical devices.
These electronic devices provide both advantages and challenges to the personnel operating them. Many of these electronic devices may be capable of autonomous or semi-autonomous motion of one or more articulated arms, end effectors and/or imaging devices. When the articulated arms and/or the end effectors include redundant degrees of freedom (i.e., more than the six degrees of freedom typically associated with Cartesian x, y, and z positioning and roll, pitch, and yaw orientations), the articulated arms and/or the end effectors may provide extensive flexibility in adjusting to changes in patient size, position, and/or orientation as the articulated arms and/or the end effectors are used to support medical procedures. This is possible because the redundant degrees of freedom allow the articulated arms and/or the end effectors to be positioned so as to avoid collisions among themselves, the patient, and/or other devices and personnel in an operating room and/or interventional suite.
Many medical procedures call for high precision in the positioning, orientation, and/or stability of the medical tools and/or devices used to perform the procedures. Computer-assisted medical devices with articulated arms have been used for years to perform high precision medical procedures, with the vast majority of these procedures being performed in the abdomino-pelvic cavities of the patient. There are many reasons for this including the large variety of possible abdomino-pelvic procedures and the characteristics of the anatomy of the abdomino-pelvic region, just to name a few. In some cases, a contributing factor may also be related to the realistic limitations of the computer-assisted medical devices and their articulated arms. In some examples, an articulated arm may have a practical upper limit on the amount of force and/or torque that the articulated arm may exert on a tool tip or end effector located at the distal end of the articulated arm due to such factors as the length of the articulated arm, the mass of the tool tip and/or end effector, the size of the actuators of the articulated arm, and/or the like. In some examples, the electro-mechanical systems of the articulated arm, the end effector, and/or the tool tip may also be subject to small oscillations and/or vibrations that may result in less than desirable vibrations in the tool top and/or the end effector. In some examples, the oscillations or vibrations may vary based on the mass of the end effector, tool tip, and/or imaging device located at the cantilevered end of the articulated arm and/or the position of the articulated arm.
In many circumstances, laparoscopic procedures with manually operated laparoscopic instruments may be subject to similar limitations. In many cases, a patient may introduce additional conditions that a stand-alone teleoperated system may not have. In some examples, physiological motions associated with respiration, heart beats, and/or the like may introduce motion to the end effector, tool tip, and/or imaging device that may be less than desirable as well.
During some procedures, the operator of the computer-assisted medical device may be able to suitably compensate for the oscillations and/or vibrations as long as the amplitude and/or frequency are not too large. In some examples, compensating for the oscillations and/or vibrations may significantly increase the fatigue of an operator.
In general, however, the limitations of the computer-assisted medical device and its articulated arms may be reduced and/or substantially eliminated during abdomino-pelvic procedures because of how the tool tips, end effectors, and/or imaging devices (such as an endoscope) pass through the body wall of the patient. During many procedures, the tool tips, end effectors, and/or imaging devices are passed through a hollow cannula that is inserted through an incision in the patient. The skin and the abdominal wall of the patient act on the cannula to both stabilize the tool tips, end effectors, and/or imaging devices and to absorb the vibrations. For minimally invasive medical procedures where there is a non-compliant body wall supporting the cannula (e.g., through the ribs in cardiac and thoracic procedures), a non-circumferential retainer on the cannula (e.g., procedures where multiple cannulas go through the same larger incision, such as transaxial thyroidectomy), a thin or frail body wall (e.g., pediatric or elderly patients), or no constraint/body wall at all (e.g., transoral, transanal, transvaginal, eye surgery, or extremity reconstructive procedures) the body wall alone may not be able to provide sufficient stabilization and/or vibration absorption to support many medical procedures where precision is important.
Stabilization and/or vibration reduction may be improved through the use of tool jigs that are attached to the patient or surgical table, mounted on table-side stands, mounted to ceiling fixtures, and/or the like. Many of these tool jigs, however, may have limitations in their degrees of freedom, size, and/or the like that significantly limit their ability to be used with patients of different sizes, different positions within the anatomy of the patients, interacting with different ancillary equipment, and/or with different procedures. These tool jigs may also have a limited ability to adapt to changes in patient position and/or orientation during a procedure. Additional flexibility may be obtained by using different tool jigs for different procedures, but the number of possible patients, positions, and/or procedures may involve an unacceptably large number of tool jigs.
Accordingly, it would be advantageous to develop systems and methods for vibration reduction and stabilization of the articulated arms, end effectors, and/or tool tips of computer assisted medical devices.